hibernate最初印象---helloworld的实现
最近，由于种种原因，开始接触hibernate，今天实现了第一个hibernate的入门程序，也就是经典的helloworld，个人喜欢在框架学习的时候，把最基本的helloworld程序的开发过程详细的写下来，以备日后搭建环境时作为参考，步入正题，说说hibernate的helloworld的开发。
以贴图为主，先来看看hibernate工程的目录结构
目录的结构很清晰，额外说一句，我是采用的hibernate4的jar包，具体下载，详见hibernate官网的下载目录，还有我采用的是mysql的数据库，所以，mysql的连接jar文件必不可少
Studnet是一个model，具体实现，参见下面代码
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package com.bjsxt.hibernate.model;public class Student {private int id;private String name;private int age;public int getId() {return id;}public void setId(int id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getAge() {return age;} public void setAge(int age) {this.age = age;}}?
?hibernate的配置文件
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<?xml version='1.0' encoding='utf-8'?><!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"><hibernate-configuration> <session-factory> <!-- Database connection settings --> <property name="connection.driver_class">com.mysql.jdbc.Driver</property> <property name="connection.url">jdbc:mysql://localhost:3306/hibernate</property> <property name="connection.username">root</property> <property name="connection.password">mlc</property> <!-- JDBC connection pool (use the built-in) --> <!-- <property name="connection.pool_size">1</property> --> <!-- SQL dialect --> <property name="dialect">org.hibernate.dialect.MySQLDialect</property> <!-- Enable Hibernate's automatic session context management --> <!-- <property name="current_session_context_class">thread</property> --> <!-- Disable the second-level cache --> <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property> <!-- Echo all executed SQL to stdout --> <property name="show_sql">true</property> <!-- Drop and re-create the database schema on startup --> <!-- <property name="hbm2ddl.auto">update</property> --> <mapping resource="com/bjsxt/hibernate/model/Student.hbm.xml"/> </session-factory></hibernate-configuration>
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hibernate的映射关系配置文件
? ?<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"><hibernate-mapping package="com.bjsxt.hibernate.model"> <class name="Student" table="student"> <id name="id"> </id> <property name="name"/> <property name="age"/> </class></hibernate-mapping>
?用于测试hibernate的java类
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package com.bjsxt.hibernate.model;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.cfg.Configuration;public class StudentTest {/** * @param args */public static void main(String[] args) {// TODO Auto-generated method stubStudent stu = new Student();stu.setAge(2);stu.setId(2);stu.setName("mlc");Configuration cf = new Configuration();SessionFactory sf = cf.configure().buildSessionFactory();Session session =sf.openSession();session.beginTransaction();session.save(stu);session.getTransaction().commit();session.close();sf.close();}}?
?运行结果
??2011-12-22 10:34:13 org.hibernate.annotations.common.Version <clinit>
INFO: HCANN000001: Hibernate Commons Annotations {4.0.0.CR2}2011-12-22 10:34:13 org.hibernate.Version logVersionINFO: HHH000412: Hibernate Core {4.0.0.CR5}2011-12-22 10:34:13 org.hibernate.cfg.Environment <clinit>INFO: HHH000206: hibernate.properties not found2011-12-22 10:34:13 org.hibernate.cfg.Environment buildBytecodeProviderINFO: HHH000021: Bytecode provider name : javassist2011-12-22 10:34:13 org.hibernate.cfg.Configuration configureINFO: HHH000043: Configuring from resource: /hibernate.cfg.xml2011-12-22 10:34:13 org.hibernate.cfg.Configuration getConfigurationInputStreamINFO: HHH000040: Configuration resource: /hibernate.cfg.xml2011-12-22 10:34:13 org.hibernate.internal.util.xml.DTDEntityResolver resolveEntityWARN: HHH000223: Recognized obsolete hibernate namespace http://hibernate.sourceforge.net/. Use namespace http://www.hibernate.org/dtd/ instead. Refer to Hibernate 3.6 Migration Guide!2011-12-22 10:34:13 org.hibernate.cfg.Configuration addResourceINFO: HHH000221: Reading mappings from resource: com/bjsxt/hibernate/model/Student.hbm.xml2011-12-22 10:34:13 org.hibernate.internal.util.xml.DTDEntityResolver resolveEntityWARN: HHH000223: Recognized obsolete hibernate namespace http://hibernate.sourceforge.net/. Use namespace http://www.hibernate.org/dtd/ instead. Refer to Hibernate 3.6 Migration Guide!2011-12-22 10:34:13 org.hibernate.cfg.Configuration doConfigureINFO: HHH000041: Configured SessionFactory: null2011-12-22 10:34:13 org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl configureINFO: HHH000402: Using Hibernate built-in connection pool (not for production use!)2011-12-22 10:34:13 org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl configureINFO: HHH000115: Hibernate connection pool size: 202011-12-22 10:34:13 org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl configureINFO: HHH000006: Autocommit mode: false2011-12-22 10:34:13 org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl configureINFO: HHH000401: using driver [com.mysql.jdbc.Driver] at URL [jdbc:mysql://localhost:3306/hibernate]2011-12-22 10:34:13 org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl configureINFO: HHH000046: Connection properties: {user=root, password=****}2011-12-22 10:34:14 org.hibernate.dialect.Dialect <init>INFO: HHH000400: Using dialect: org.hibernate.dialect.MySQLDialect2011-12-22 10:34:14 org.hibernate.engine.transaction.internal.TransactionFactoryInitiator initiateServiceINFO: HHH000399: Using default transaction strategy (direct JDBC transactions)2011-12-22 10:34:14 org.hibernate.hql.internal.ast.ASTQueryTranslatorFactory <init>INFO: HHH000397: Using ASTQueryTranslatorFactoryHibernate: insert into student (name, age, id) values (?, ?, ?)2011-12-22 10:34:14 org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl stopINFO: HHH000030: Cleaning up connection pool [jdbc:mysql://localhost:3306/hibernate]?
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基本就这些了，做点备注吧
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首先，本身的目录的结构是约定俗称的一种配置，包括文件的命名其次，hibernate的映射文件，必须保证要数据库中要有相应的表与之对应，或者名称是对应的，或者，自行指定也可以最后，hibernate的映射文件中，id是代表了表的主键值，property是其它的属性值特别提醒： 对于配置文件，最好还是从原始的参考文档中直接复制粘贴，而不要自己敲或者其它什么的，没啥技术含量，而且容易出错
如果在细节上，有什么问题，可以针对性的交流?
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1 楼 freedxz 2012-05-18 好几个 WARN 不处理一下？ 2 楼 mlc0202 2012-05-18 freedxz 写道好几个 WARN 不处理一下？